Package overview

Lentil is a Python library for modeling the imaging chain of an optical system. It was originally developed at NASA’s Jet Propulsion Lab by the Wavefront Sensing and Control group (383E) to provide an easy to use framework for simulating point spread functions of segmented aperture telescopes.

Lentil provides a framework for defining optical planes and combining them to model diffraction and other imaging effects. It can be used to create models with varying levels of complexity; from simple prototypes to extremely high-fidelity models of ground or space telescopes. Lentil was developed to be:

  • User friendly - a simple, consistent interface optimized for common use cases.

  • Modular - models are made by combining configurable building blocks. It is easy to replace or update individual elements without impacting the rest of the model.

  • Easy to extend - core objects are designed to be subclassed, modified, extended, broken apart, and put back together in different ways.

Lentil organization

Lentil is organized into two parts: a standard library and a few subpackages providing domain-specific tools. The features of the standard library and each of the subpackages is described in the table below:




Standard library


Model focal planes


Work with spectral data

Lentil’s standard library can be imported as follows:

>>> import lentil

If you’d prefer to use Lentil en français, you can try

>>> import lentil as le

Public subpackages are automatically imported with Lentil.

Getting help

The best place to ask for help on subjects not covered in this documentation or suggest new features/ideas is by opening a ticket on Github.


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